@article{Rackoff:VAS:TCS:1978,
    Author = {Rackoff, Charles},
    File = {The covering and boundedness problems for vector addition systems - Rackoff (0) (0) - a - a - o.pdf},
    ISSN = {0304-3975},
    Journal = {Theoretical Computer Science},
    Keywords = {vector addition systems and Petri nets and classic and readme},
    Number = {2},
    Pages = {223 - 231},
    Title = {The covering and boundedness problems for vector addition systems},
    URL = {http://www.sciencedirect.com/science/article/pii/0304397578900361},
    Volume = {6},
    Year = {1978},
    bdsk-url-1 = {http://www.sciencedirect.com/science/article/pii/0304397578900361},
    bdsk-url-2 = {http://dx.doi.org/10.1016/0304-3975(78)90036-1},
    date-added = {2012-12-18 17:08:36 +0000},
    date-modified = {2015-03-26 17:40:27 +0000},
    doi = {10.1016/0304-3975(78)90036-1}
}

@article{Rackoff:VAS:TCS:1978, Author = {Rackoff, Charles}, File = {The covering and boundedness problems for vector addition systems - Rackoff (0) (0) - a - a - o.pdf}, ISSN = {0304-3975}, Journal = {Theoretical Computer Science}, Keywords = {vector addition systems and Petri nets and classic and readme}, Number = {2}, Pages = {223 - 231}, Title = {The covering and boundedness problems for vector addition systems}, URL = {http://www.sciencedirect.com/science/article/pii/0304397578900361}, Volume = {6}, Year = {1978}, bdsk-url-1 = {http://www.sciencedirect.com/science/article/pii/0304397578900361}, bdsk-url-2 = {http://dx.doi.org/10.1016/0304-3975(78)90036-1}, date-added = {2012-12-18 17:08:36 +0000}, date-modified = {2015-03-26 17:40:27 +0000}, doi = {10.1016/0304-3975(78)90036-1} }